Byelaw 49 - Workboats

Workboats, tugs and multi-cats currently under the licence of the PLA (Sec 124), have a number of options as to how to remain compliant. Under the proposed amendment, other commercial vessels not under international rule or Sec124 could also use these options.

Compost / Cassette Toilets

Compost Toilets separate solid and liquid waste so that the solid waste breaks down under aerobic conditions to 10-30% of its original volume. The liquid element is still "sewage" and must not be discharged to water or within 10m of a watercourse. A large advantage of compost toilets is that they do not consume water.

There are currently no British or European Standards covering Composting Toilets. The Environment Agency Pollution Prevention Guideline Number 4 (PPG4) on treatment and disposal of sewage where no foul sewer is available noted that the fluid fertiliser (urine) and dry compost (faecal matter broken-down under aerobic conditions) should not be discharged to a watercourse. Although this Guidance Note has been withdrawn (as the EA no longer provide "good practice" guidance) the requirements set out within the document should still be followed.

We recommend that you read the Environment Agency position statement on using composting toilets and the resulting compost (see Useful Links below).

Cassettes should only be emptied into a designated disposal point not into the Thames or other watercourses.

Install tank and routinely pump-out to a suitable receiver

Installation of a tank will necessitate this being pumped out to a suitable facility.

Treatment

There are small treatment facilities that may be applicable for larger workboats, tugs and multicats, especially if tanks are available. The smallest system deals with 2000litres in a day and can fit in the same space as a washing machine would need. For more detail about compliance via treatment see this link.